The present invention relates to a vehicle seat, especially an aircraft passenger seat, with a seat component and a backrest displaceable relative to each other by one adjustment device. The adjustment device has a plurality of moving joints connected to each other, at least partially by a bar-type supporting frame. Individual bar parts position the seat component upright relative to an aircraft or cabin deck, and execute a traversing movement by means of an actuating device in such a way that the seat component maybe moved from an initial position to at least one additional position and vice versa. The moving joints are mounted at least in part at the corner points of the bar-type supporting frame. At least one moving joint is provided in the area of the transition between backrest and seat component.
On very prolonged trips for long-range flights or for travel by ship, for example, by ferry, it is a general aim of aircraft or ferry outfitters to increase the comfort of seat occupants and the passengers to be transported. Customers, especially in the first-class and business-class areas, have their own ideas regarding seat comfort. The trend is to accommodate the wishes of passengers who want to be able to use their travel time for meaningful rest or sleep, for example, in order to counteract fatigue phenomena at their destination after a long-range flight.
DE 675 982 C discloses a generic aircraft seat with a bar-type supporting frame resembling a so-called guide rod parallelogram. The guide rod parallelogram in question makes it possible to adjust a vertically adjustable aircraft pilot seat. The seat simultaneously is pivotable about an axis mounted transversely to the direction of flight and permits longitudinal adjustment, separately about the transverse axis in each vertical or longitudinal setting. For this purpose, in the case of the conventional solution, an upper rigid bar part is connected by moving joints both to the seat component and to the backrest. Extending parallel to the upper rigid part is a lower rigid bar part of the conventional bar-type supporting frame from a seat rail longitudinal adjustment device to other bar parts to which the rear area of the backrest is engaged by moving joints. The lower rigid bar part is also connected to the indicated structural components by moving joints mounted on the lower bar on the end side. The conventional bar-type supporting frame increases the size of the pilot""s seat, so that its use in the cabin area of an aircraft with cramped installation conditions appears unreasonable. In addition, the bar-type supporting frame engages the movable seat components of the pilot""s seat in such a way that adjustment options are provided only within a very narrow range. For example, a sleeping or reclining position option is also precluded, which option not being desirable for aircraft pilots. As a result of the specific structural embodiment, the conventional bar-type supporting frame is also not capable of absorbing the forces introduced into the seat structure in the event of a crash. Consequently, failure of the structure might be expected in the event of a crash.
In contrast, subsequently published EP 1 074 468 A2 discloses a distinctly improved aircraft passenger seat which permits assumption of different positions, including a reclining position and a sleeping position. In the sleeping position, the upper sides of the backrest, seat component, and legrest form a more or less level reclining surface. A longitudinally adjustable bar part, which may be telescoped to various positions to swivel the backrest by means of an actuating device, engages the lower third of the backrest.
In addition, the backrest may be mounted by a moving joint on the seat component in the area of transition between the moving joint and the seat component. The respective moving joint in the transitional area is in turn movable in a longitudinal guide. The longitudinal guide extends more or less horizontally and is made up of components of armrests of the aircraft passenger seat. When mounted to be stationary, the armrests delimit on either side the longitudinal sides of the passenger seat which otherwise may be adjusted to various positions. If another actuating mechanism engages the front bar part which on the end side is hinged to the deck of the cabin and to the bottom of the seat component in its front area and accordingly the front bar part pivots, the seat may assume its individual positions and is forced along the armrests by way of the longitudinal guides. Consequently, the solution disclosed in the European patent application does not make use of any bar-type supporting frame. Rather, such solution depends on forced guiding for the process of movement. As a result of the diagonal mounting of the rear, variable-length bar part, which engages the backrest in the lower third of the rear area, much structural space is in turn wasted, since it is necessary to secure the movable components by way of a separate cover so that the leg area of the next seat occupant to the rear will not be interfered with or even injured.
Objects of the present invention are to provide improved seating systems having increased requirements for the convenience and seating comfort of passenger, while the systems take up little structural space and meet the more stringent requirements set for crash safety.
The foregoing objects are basically attained by passenger seats having the respective moving joint connected in the transition area to one end of the upper bar part extending along the seat component and to the end of a rear bar part. The other end of the upper bar part is connected by another moving joint to a front bar part. The rear and the front bar parts position the seat component at least partly upright relative to the floor. At least the front bar part or the rear bar part is longitudinally adjustable. The number of possible movements, and accordingly the degree of freedom relative to the conventional solutions is distinctly increased as a function of the number of moving joints and bar parts of the bar-type supporting frame. The seat component and the backrest may be positioned over a very wide range of settings. In this situation, the bar-type supporting frame with its rigid and longitudinally partly adjustable bar assumes exclusively the function of a guide for the entire movement concept. Additional forced guides inherently restrict adjustability and may be abandoned in their entirety.
In addition, the seat kinematics of the present invention permit use of the traversing movement of the seat component to at least one of the additional positions to lower the seat component relative to its initial position. The seat component then assumes an inclined position to bring about a reclining position for the seat occupant. In the process, the backrest automatically follows the slope of the seat component. As a result of the pivoting movement of the bar-type supporting frame in such a way, an overall reclining surface extending obliquely is achieved as a reclining position for the seat occupant. The otherwise conventional function of the vehicle or aircraft passenger seat is accordingly transformed into that of a full sleeping area for resting or sleeping. If in the process the legrest, guided by the bar-type supporting frame, automatically follows the movement of seat component and backrest, the obliquely extending reclining surface is extended downward into the foot area so that the sleeping area can thus be completed. Since the entire bar-type supporting frame is situated more or less below the seat component, the present invention conserves structural space and to this extent is particularly well suited under confined installation space conditions such as are present in aircraft or the like. Production of the bar-type supporting frame with its bar parts results, especially in the base position with the backrest fully upright, in a compact structural unit. Its bar components ensures that if any crash forces are introduced into the seat, they will be reliably absorbed and may be diverted into the vehicle floor or cabin deck without breaking off of parts of the bar-type supporting frame or even collapse of the seat components, which are kept apart by the fixed bar-type supporting frame.
Preferably, between the initial position and the reclining position, at least one other comfort position can be adjusted in which the rear seat component surface is lowered relative to the front seat component surface. This position is conducive to relaxed working. Stress on the legs in the forward resting area with the seat component can be accordingly relieved by the raised position. The indicated adjustment processes can be effected in an economical manner with only a few components. Thus, a vehicle seat according to the present invention can be produced economically and is structurally light. The lightness is useful in aircraft in helping to avoid unnecessary weight.
The vehicle seat of the present invention need not be limited in use to an aircraft passenger seat. It can also be used aboard ships, for example in ferry operation, or in other modes of travel, such as trains or busses.
Preferably, the actuators used are driven pneumatically to produce the motion for the adjustment device. Optionally transient processes in the adjustment of the seat element to one another is cushioned by piston-cylinder units with pneumatic dampers. Furthermore, in one preferred embodiment of the vehicle seat of the present invention, the adjustment device at least with the seat component and backrest can be built as modular components. Such modular components can then be joined to other seat component elements, such as the seat side parts, to armrests, or the like for subsequent seat use by pallet delivery on site, for example in the aircraft. This also has the advantage that, when the seating is changed, for example when the intended number of seats is increased in the same area, the luxury vehicle seats of the present invention can be changed into conventional seats without an expanded reclined position. Furthermore, the seat component and backrest surface which is subject to greater wear can be cleaned or repaired elsewhere, and for example, can be provided with a new covering material. The seat components which are otherwise less subject to wear or dirt and which are also called compartments in technical language can then remain in the respective vehicle, for example in the aircraft, and can be equipped there in very short time with a new or maintained adjustment device with the seat component and backrest.
Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention.